Quoz

Question 0

What does a magneto check indicate?

Answer 0

The changes and drops on rpm for each check give an indication of the operational condition of the engine, as well as magnetos

Question 1

How do you perform a mag check?

Answer 1

The engine must be at operating temp.
Increase rPm smoothly to whatever rpm is specified in the POH
Carefully turn ignition switch from both position to the left position
Note rpm drop and smoothness of engine and then return to both
Next turn engine from both to right, note rpm drop and smoothness of condition, return to both.

Question 2

What is a smooth drop of approximately 125-150 rpm

Indicative of?

Answer 2

Normal engine operation

Question 3

What is a smooth drop greater than 150 rpm indicative of?

Answer 3

A mixture that is either too lean or too rich, of a magneto that is slightly out of
time

Question 4

What does a rough drop of greater than 150 RPM and or a rough running engine indicate?

Answer 4

A bad ignition lead, bad spark plug, magneto that is far out of time

Question 5

What does no drop on one mag and the engine shutting off on the other mag indicate?

Answer 5

A shorted p-lead or an inoperative mag on the side that shuts off

Question 6

What does no drop on one mag and normal drop on the other mag indicate?

Answer 6

An open p lead or an open in the ignition switch on the side that shows no drop.

Question 7

What does general inspection of a magneto consist of?

Answer 7

Security of the mag
Cracks In case
Burned or broken wires
Oil in the drive end seal 
Carbon tracking in the distributor block 
Look for oil in the cam area

Question 8

What does normal wear of points look like?

Answer 8

Even, dull gray and frosted in appearance

Question 9

What are some discrepancies to look for with a points inspection?

Answer 9

Burned appearance, large pits or transfer of materials.

Question 10

How do you check for moistness of a felt follower?

Answer 10

By squeezing between two fingers

Question 11

What kind of electrical inspections should be done?

Answer 11

Ignition coil

Capacitor

Question 12

What are inspections on the ignition coil done on?

Answer 12

Primary coil winding for continuity and resistance.
Secondary coil winding for continuity and resistance.
Firing test-leakage
Gap test- how far the spark will jump

Question 13

What things should the capacitor be inspected for?

Answer 13

Condenser capacity in microfarads
Series resistance
Condenser leakage

Question 14

What does condenser capacity

Affect?

Answer 14

Timing of how quickly the condenser fills up.

Question 15

What are the steps to magneto overhaul?

Answer 15

Disassembly, cleaning, inspection and repair, assembly, testing.

Question 16

What two things must be accomplished with magneto timing?

Answer 16

Set points to open at e-gap
Mesh distributor gear so that the points open as the distributor finger on crossing the high tension post in the distributor block

Question 17

How is eGap found on most bendix single mags?

Answer 17

By using a timing scale and pointer.

Question 18

What are the two ways points are set to open in a bendix single mag?

Answer 18

By rotating the cam or pivoting the points

Question 19

How is eGap found on slick mags?

Answer 19

By using the t150 timing tool.

Question 20

How are the points set to open in a slick mag? The gears meshing?

Answer 20

Pivoting the points, gears are set by timing marks.

Question 21

How are the points set to open on a dual mag?

Answer 21

Usually one set of points are set by rotating the cam, and the other is set by pivoting the points.

Question 22

What two things must be accomplished by external magneto timing?

Answer 22

The magneto must be set to fire to a given cylinder, the engine must be in the position (BTDC) for ignition to occur at that cylinder.

Question 23

Describe the process of external mag

Timing.

Answer 23

The mag must be placed at eGap, win the distributor finger aligned with the tension terminal for the #1 cylinder.
To keep the engine in position for ignition to occur at the prescribed cylinder, the engine must be the prescribed number of degrees before tDC on the compression stroke
To find that compression stroke, removed
One spark plug from each cylinder
Place the piston the prescribed number of degrees
Before tDC

Question 24

Why would you remove one spark plug

From a cylinder when trying to find compression stroke?

Answer 24

To make it easier to move the prop,

And for safety